Distributed AD

1)Distributed AD offers improved scalability, performance, and resource utilization by allowing workers of the same AD session to be started on additional middle tier systems.

2)AD has always utilized a Parallel Jobs System, where multiple AD workers start and are assigned jobs. Information for the Jobs System is stored in the database, and workers receive their assignments by monitoring certain tables in the database.

3) Distributed AD allows workers to be started on remote machines, where they can utilize the resources on the remote machines when completing their assigned jobs


Prerequistes
1) Shared APPL_TOP
2) AD.H


Working
On one of your shared APPL_TOP nodes, start your AutoPatch or AD Administration session with the following command line options:

localworkers= workers=
For example to run an AutoPatch session with 3 workers on the local node and 5 workers on a remote node:

adpatch localworkers=3 workers=8
On one or more of the additional shared APPL_TOP nodes, start an AD Controller session with the following command line option:

adctrl distributed=y

After providing basic information, AD Controller will prompt for the worker number(s) to be started. For example, enter "4 5 6 7 8" or "4-8" to start workers 4 through 8. If AD Controller is started prior to AutoPatch or AD Administration starting the Jobs System, AD Controller will ask if you want to wait. Choosing yes will cause AD Controller to wait until the Jobs system is started, at which point it will start the appropriate worker processes. If an AutoPatch session has already been started, AD Controller will wait automatically.



Example of a two node session with five workers:

Node 1) adpatch localworkers=30 workers=20

Node 2) adctrl distributed=y and choose Enter the worker range 21-30
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Source:-http://appsoracle.blogspot.com/2011/07/distributed-ad.html
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